Hydrogen peroxide-based skin disinfectant

ABSTRACT

A skin disinfectant in ready-to-use concentrated liquid or dry powdered form. Ready-to-use liquid forms have a pH of from about 2 to about 6 and include: (a) hydrogen peroxide in a concentration of from about 0.01 to about 4% w/w of the solution; (b) at least one surfactant chosen from imidazoline derivatives, alkyl betaines, alkyl amidopropyl betaine amides, alkyl amidopropyl betaines, alkylsulfo betaines, amine oxides and derivatives thereof in a concentration of from about 0.01 to about 15% w/w of the solution; (c) at least one hydrogen peroxide stabilizer in a concentration of from about 0.01 to about 4% w/w of the solution; (d) at least one member chosen from cyclic carboxylic acids and salts thereof in a concentration of from about 0.01 to about 4% w/w of the solution; and (e) at least one skin conditioning agent in a concentration of from about 0.01 to about 10% w/w of the solution.

This application claims the benefit of U.S. provisional application No.60/570,807, filed May 14, 2004 under 35 U.S.C. 119 (e).

FIELD OF THE INVENTION

The present invention relates to disinfecting solutions or formulationsfor use on skin containing hydrogen peroxide.

BACKGROUND OF THE INVENTION

Infection control is a major concern for health care professionals.Viruses and bacteria on contaminated hands are easily spread amongpeople in health care facilities such as hospitals. Of course, the riskof infection is also present in public places other than hospitals, suchas in gyms, washrooms, restaurants, and schools.

Washing hands with detergents or soaps is a way to reduce the risk ofinfection. However, in certain environments, such as hospitals, thelevel of disinfection required cannot be achieved by most commonproducts. Consequently, hand disinfectants have been developed toachieve higher levels of disinfection where the need exists. These typesof products generally contain alcohols, iodinesaodophors, chlorhexidinegluconate (CHG), phenolic compounds, quaternary ammonium compounds orcombinations thereof.

A problem with existing products is that they often sacrificedisinfectant activity for the sake of skin mildness or vice versa. Forexample, while raising the concentration of the active ingredient maylead to a higher level of disinfection, such higher concentrationfrequently leads to increased skin irritation.

As well, many common disinfecting ingredients have inherentdisadvantages. For example, while alcohols are effective in providingrapid rates of disinfection, they are flammable and therefore give riseto safety risks in use and storage. As defatting agents, they can causedry, chapped or cracked skin on repeated use. Furthermore, theiranti-microbial activity is dependent on concentration and tends to dropdramatically when used on wet hands resulting in insufficient germ kill.To overcome some of these disadvantages, it is known to includeadditional ingredients such as emollients, humectants, and surfactants.For example, U.S. Pat. No. 6,617,294 to Narula et al. issued Sep. 9,2003 discloses a waterless disinfecting hand cleanser made of acombination of 60 to 90% w/w of an alcohol, silicone based materials,and humectants.

Parachlorometaxylenol (PCMX) and triclosan are common phenolic compoundsused in antiseptic hand wash solutions. See, for example, Europeanpatent 505,935 B1, assigned to Becton, Dickinson and Company and grantedon Feb. 4, 1998, which discloses an anti-microbial skin formulationcontaining PCMX, a block copolymer, and a lauryl sulfosuccinate.Although PCMX and triclosan have lower toxicity than other phenols, andare rather mild to the skin, their germicidal activity is low anddepends on the formulation ingredients.

Iodine and iodophors have been used in antiseptic hand wash formulationsfor a long time. Their germicidal activities are low and reduced in thepresence of organic matter. Furthermore, these ingredients are toxic andcan irritate and stain skin.

Chlorhexidine gluconate (CHG) is used as a skin cleanser, pre-surgicalscrub, germicidal hand rinse, and wound cleaner. It is less effectiveagainst gram-negative bacteria as compared to gram-positive bacteria andexhibits relatively low germicidal activity.

Hydrogen peroxide is a broad-spectrum germicide effective againstbacteria, yeast, fungi, viruses and spores. It is non-toxic and itsbreakdown products, oxygen and water, are innocuous thus making it safeto the environment. At low concentrations (e.g. 3% w/w), it isnon-irritating to skin, but exhibits low germicidal activity. Forexample, a solution containing 3% w/w hydrogen peroxide takes 20 minutesto achieve a greater than 6 log reduction in Staphylococcus aureus,which is too long for many applications. Increasing the concentration ofhydrogen peroxide will increase the rate of disinfection. For example, a25% w/w aqueous solution of hydrogen peroxide requires only 20 secondsto achieve a greater than 6 log reduction in Staphylococcus aureus.However, the solution is corrosive at this concentration and requiresspecial handling procedures.

While skin disinfecting formulations exist, there is still a need fornew formulations that are both safe and capable of achieving aneffective rate of disinfection at realistic contact times. The presentinvention is intended to meet this need.

SUMMARY OF THE INVENTION

The invention provides, in accordance with a first aspect, an aqueousskin disinfecting solution having a pH of from about 2 to about 6, about2.5 to about 5, or about 3 to about 5, and comprising:

-   -   (a) hydrogen peroxide in a concentration of from about 0.01 to        about 4% w/w, from about 0.25 to about 3% w/w, or from about 1        to about 3% w/w, of the solution;    -   (b) at least one surfactant chosen from imidazoline derivatives,        alkyl betaines, alkyl amidopropyl betaines, alkyl amidopropyl        betaine amides, alkylsulfobetaines, amine oxides, and        derivatives thereof, in a concentration of from about 0.01 to        about 15% w/w, from about 0.3 to about 10% w/w, or from about 1        to 5% w/w, of the solution;    -   (c) at least one hydrogen peroxide stabilizer in a concentration        of from about 0.01 to about 4 % w/w, from about 0.01 to about 3%        w/w, from about 0.01 to about 2% w/w, or from about 0.1 to 0.5%        w/w, of the solution;    -   (d) at least one member chosen from cyclic carboxylic acids and        salts thereof in a concentration of from about 0.01 to about 4%        w/w, or from about 0.05 to about 1% w/w, of the solution;    -   (e) at least one skin conditioning agent in a concentration of        from about 0.01 to about 10% w/w, or from about 0.5 to about 4%        w/w, of the solution.

Preferred imidazoline derivatives are alkylamphocarboxylates andalkyliminocarboxylates.

The hydrogen peroxide stabilizer can be chosen from phosphoric acid,phosphonic acids having 1 to 5 phosphonic acid groups, e.g.1-hydroxyethylidene-1,1,-diphosphonic acid, amino tri(methylenephosphonic acid), diethylenetriaminepenta(methylene phosphonic acid),2-hydroxy ethylimino bis(methylene phosphonic acid), and ethylenediamine tetra(methylene phosphonic acid). They can also be chosen fromsodium tripolyphosphate, ethylenediaminetetraacetic acid (EDTA),diethylenetriaminepentaacetic acid (DTPA),N-(hydroxyethyl)-ethylenediaminetriacetic acid (HEDTA), nitrilotriaceticacid (NTA), 2-hydroxyethyliminodiacetic acid (HEIDA), benzoic acid,aminobenzoic acid, citric acid, iminodisuccinic acid, polyaspartic acid,and salts thereof.

The cyclic carboxylic acid can be chosen from furan carboxylic acid(e.g. 2-furan carboxylic acid), benzoic acid and salicylic acid.

The skin-conditioning agent can be chosen from glycerides, sorbitol,castor oil, allantoin, cationic polymers, lanolin and its derivativesand cetyl alcohol.

The solution can further comprise at least one buffer, in aconcentration of from about 0.01 to about 5% w/w of the solution, chosenfrom citric acid, lactic acid, glycolic acid, phosphoric acid, malicacid, succinic acid and tartaric acid.

In other embodiments, the solution can comprise at least one optionalhydrogen peroxide compatible surfactant in a concentration of from about0.01 to about 10% w/w of the solution. Exemplary hydrogen peroxidecompatible surfactants are alkyl sulfate, alkyl ether sulfates, alkylbenzene sulfonic acids, alkyl sulfonic acids, alkyl diphenyl oxidesulfonic acids, naphthalene sulfonic acids, alkyl or alkenyl esters ordiesters of sulfosuccinic acids, and salts thereof, alcohol ethoxylates,alkyl phenol ethoxylates, fatty acid esters, and alkylpolyglucosides.

As well, the solution can comprise at least one C1 to C8 alcohol in aconcentration of from about 0.01 to about 10% w/w of solution, which maybe chosen from benzyl alcohol, ethanol, n-butanol, isopropanol andglycols.

The solution can further comprise at least one member chosen frommonocarboxylic acids, polycarboxylic acids, and mixtures thereof in aconcentration of from about 0.01 to about 3% w/w of the solution. Theseingredients have known pH buffering, stabilizing and cleaningproperties. Preferred monocarboxylic acids are glycolic acid and aceticacid. A preferred polycarboxylic acid is citric acid.

To improve the rheological properties and attractiveness of thesolution, the solution can further comprise at least one thickeningagent compatible with hydrogen peroxide (e.g. polyacrylic acid polymers,polysaccharides, and cellulose-based polymers in a concentration of fromabout 0.01 to about 5% w/w of the solution, and at least one memberchosen from dyes and fragrances (as are known in the art) in aconcentration of from about 0.001 to about 0.5% w/w of the solution.

The balance of the solution consists of deionized water, preferably witha conductivity of less than 20 micro zimens. It will be appreciated thatthe lower the deionized water conductivity, the longer the shelf life.

In accordance with a second aspect of the invention, the solution may bein concentrated liquid form for dilution by the end user. Similarly, inaccordance with a third aspect, the invention may take the form of a drypowdered formulation, which can be dissolved in water to form a solutionaccording to the first aspect.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

When used herein, the expression “consisting essentially of” shallmean—including the listed ingredients and such additional ingredients aswould not materially affect the basic and novel properties of theinvention—. The basic and novel properties are the disinfectingproperties of the invention and the suitability of the invention for useon skin.

The term “comprising” shall mean—including but not limited to—.

A “skin-conditioning agent” is any ingredient or compound, which is usedto make the solution suitable for use on skin and includes moisturizers,emollients and humectants.

Certain ingredients used in the present inventive solution can servemore than one function. For example, phosphoric acid and citric acid areboth hydrogen peroxide stabilizers and buffers. Similarly, benzoic acidis also a hydrogen peroxide stabilizer and a cyclic carboxylic acid,which contributes to disinfecting activity.

The inventive solution is able to provide adequate levels ofdisinfection while not irritating skin. The solution is non-irritatingdue to the low levels of hydrogen peroxide, mild surfactant package andlow concentrations of other mild additives employed. The solution hasbroad-spectrum activity, the degree of which is unexpected given thegermicidal activity of the individual ingredients. A synergy existsamongst the ingredients of the present inventive solution such that aneffective disinfectant is provided that is suitable for use on skin.

Commercial solutions having hydrogen peroxide concentrations of fromabout 10 to about 50% w/w, (e.g. about 35% w/w or about 50% w/w), may beused to prepare solutions according to the invention. Such commercialsolutions typically contain additional stabilizers and additives as areknown in the art and are available from manufacturers such as FMC andDegussa AG.

As mentioned above, the invention may be in the form of a concentratedliquid for dilution by the end user. Alternatively, it may be in theform of a dry formulation for dissolution in water. In such dryformulation, the hydrogen peroxide may be supplied by persalt compounds,of which sodium percarbonate and sodium perborate in its monohydrate andtetrahydrate forms are preferred. Since sodium percarbonate containsabout 20% hydrogen peroxide by weight, and sodium perborate monohydrateand sodium perborate tetrahydrate contain about 30% and about 20%respectively by weight, proper allowance must be made when blending thedry mixture of components to achieve the desired levels of hydrogenperoxide upon dissolution in water.

As noted above, certain surfactants are essential to the presentinvention, including, imidazoline derivatives (e.g. alkylamphoacetates,alkylamphopropionates, and alkyliminopropionates), alkylbetaines,alkylamidopropylbetaines, alkyl amidopropyl betaine amides,alkylsulfobetaines, amine oxides and derivatives and mixtures thereof.These surfactants are available from a variety of sources, includingRhodia, which manufactures and sells imidazoline derivatives inassociation with the trademark MIRANOL and an alkylamidopropylbetaine inassociation with the trademark MIRATAINE. Seppic manufactures and sellssurfactants useful in the present invention in association with thetrademark MONTALINE. Cognis manufactures and sells useful surfactants inassociation with the trademark DEHYTON. Stepan manufactures and sellsamine oxides in association with the trademark AMMONYX. Lonzamanufactures and sells imidazoline derivative and alky betaines inassociation with the trademarks AMPHOTERGE and LONZAINE.

Amine oxides useful in this invention are R1R2R3NO wherein each of R1,R2, and R3 is independently a saturated, substituted or unsubstitutedlinear or branched alkyl group having from 1 to 28 carbon atoms.

Preferred imidazoline derivatives are alkylamphocarboxylates andalkyliminocarboxylates having the following structures:

wherein R is a saturated, substituted or unsubstituted linear orbranched alkyl group having from 1 to 24 carbon atoms. Preferably, R isa linear alkyl chain having from 8 to 16 carbon atoms and R1 to R5 aresaturated, linear alkyl groups having from 1 to 3 carbon atoms.

Alkyl amidopropyl betaine amides useful in this invention have asaturated, substituted or unsubstituted linear or branched alkyl grouphaving from 1 to 24 carbon atoms. The alkyl group is preferably a linearchain having from 6 to 16 carbon atoms.

Alkyl amidosulfobetaines have the following structure:

wherein R is a saturated, substituted or unsubstituted linear orbranched alkyl group having from 1 to 24 carbon atoms. The alkyl groupis preferably a linear alkyl chain having 8 to 16 carbon atoms.

Preferred hydrogen peroxide stabilizers are available from a number ofmanufacturers including Rhodia under the trademark BRIQUEST, and Solutiaunder the trademark DEQUEST.

The invention will be better understood with reference to the followingexamples. In such examples, the following ingredients were used.

Hydrogen Peroxide

The hydrogen peroxide used in all the examples is a 50% w/w technicalgrade commercial solution sold by Degussa AG.

Hydrogen Peroxide Stabilizer

-   -   BRIQUEST ADPA 60 AW: 1-hydroxyethylidene-1,1,-diphosphonic acid,        sold by Rhodia as a 60% w/w solution.    -   BRIQUEST 301-50A: nitrilotris (methylenephosphonic acid), sold        by Rhodia as a 50% w/w solution.    -   VERSENE 100: tetrasodium ethylenediaminetetraacetate, sold by        Dow Chemicals as a 37% w/w solution.    -   VERSENE NTA 148: trisodium nitrilotriacetate, sold by Dow        Chemicals as a 38% w/w solution.    -   VERSENE HEIDA: disodium salt of 2-hydroxyethyliminodiacetic        acid, sold by Dow Chemicals as a 41% w/w solution.    -   BAYPURE CX: Sodium salt of iminodisuccinic acid, sold by Lanxess        as a 100% w/w powder.    -   BAYPURE DS: Sodium salt of polyaspartic acid, sold by Lanxess as        a 100% w/w powder.        Surfactants    -   DEHYTON MC: sodium cocoamphoacetate, sold by Cognis as a 40% w/w        solution.    -   AMPHOTERGE K-2: disodium cocamphopropionate, sold by Lonza as a        40% w/w solution.    -   AMPHOSOL CG: cocamidopropyl betaine, sold by Stepan as a 30% w/w        solution.    -   MIRANOL C2M CONC NP: cocampho diacetate, sold by Rhodia as a 30%        w/w solution.    -   MONTALINE C40: cocamidopropyl betaineamide monoethanolamine        chloride (quaternized coconut oil), sold by Seppic as a 38% w/w        solution.    -   LONZAINE 16SP: cetyl dimethyl betaine, sold by Lonza as a 35%        w/w solution.    -   MIRATAINE CBS: Cocamido propyl hydroxy sultaine, sold by Rhodia        as a 43.5% w/w solution.    -   AMMONYX LO: lauramine oxide, sold by Stepan as a 30% w/w        solution.    -   AMMONYX CDO: cocamidopropylamine oxide, sold by Stepan as a 30%        w/w solution.        Skin Conditioning Agents    -   POLYQUATERNIUM-11: cationic copolymer of vinyl-pyrrolidone and        dimethylaminoethylmethacrylate quaternized with diethyl sulfate,        sold by ISP as a 20% w/w solution.    -   POLYQUATERNIUM-7: cationic copolymer of dimethyldiallylammonium        chloride and acrylamide, sold by Mcintyre Group Ltd. as a 9% w/w        solution.    -   MERGITAL EL33: polyethylene glycol castor oil, sold by Cognis as        a 9% w/w solution.    -   Glycerin        Additional Optional Surfactants    -   STEPAN MILD SL3 BA: disodium lauryl ether sulfosuccinate        ethoxylated to 3 moles ethylene oxide (EO), sold by Stepan as a        32% w/w solution.    -   SURFYNOL 104PG-50: 2,4,7,9 tetramethyl-5 decyne-4,7 diol, sold        by Air Products as a 50% w/w solution.    -   ETHAL OA-23: Oleyl (C18) alcohol ethoxylate, 23 moles of EO/mole        of alcohol, sold by Ethox Company as a 70% w/w solution.    -   TERGITOL 15-S-7: C11-C14 secondary alcohol ethoxylate, 7 moles        of EO/mole of alcohol, sold by Union Carbide as a 100% w/w        liquid.    -   TERGITOL 15-S-5: C11-C14 secondary alcohol ethoxylate, 5 moles        of EO/mole of alcohol, sold by Union Carbide as a 100% w/w        liquid.        Thickening Agents    -   CARBOPOL 676: acrylic polymer, sold by Noveon Company as a 100%        w/w powder.    -   NATRASOL 250 HR: Hydroxyethylcellulose, sold by Hercules as a        100% w/w powder.    -   KLUCELL HF: Hydroxypropylcellulose, sold by Hercules as a 100%        w/w powder.

EXAMPLES

SOLUTION 1 INGREDIENTS % w/w Actual concentration % w/w deionized waterUp to 100 Up to 100 BRIQUEST ADPA 60 AW 0.6 0.36 salicylic acid 0.010.01 Glycerin 3 3 DEHYTON MC 3 1.2 MONTALINE C40 1 0.38 AMMONYX CDO 30.9 benzoic acid 0.2 0.2 POLYQUATERNIUM-11 0.8 0.16 MERGITAL EL33 1 0.09hydrogen peroxide 4 2 pH 4

Solution 1 is a hand disinfectant, which, at a 55% dilution achieved agreater than 4 log 10 reduction in Staphylococcus aureus and E. coli at30 second contact time using European suspension test method EN.12054.The solution was also tested against these organisms in vivo usingEuropean fingerpad test method EN.1499.

Test method EN.1499 involves preparing 2 liters of a contamination fluidcontaining from 2×10⁸-2×10⁹ test organisms. The test organisms areprepared in Tryptone Soy Broth TSB and pooled overnight. Hands arewashed with soft soap and water to remove any soil and then dried. Thehands are then immersed up to the mid-metacarpals in the contaminationfluid with the fingers spread apart. Immersion is for 5 seconds. Thehands are then air dried for 3 minutes while moving the hands to avoiddroplet formation.

Immediately after drying, the hands are sampled to establish a baselineor “pre-value” count of test organisms. This is achieved by rubbing thefingertips (including the thumb) against the base of a petri dishcontaining 10 ml TSB on a neutralization bath (designed to neutralizethe activity of the test product) for 60 seconds. A separate petri dishis used for each hand. A series of 10-fold dilutions of theneutralization bath is prepared and each dilution is plated on awell-dried Tryptone Soy Agar (TSA) plate and incubated at 37° C. for18-24 hours. The number of surviving colony forming units ofmicroorganisms on each plate is then counted and the value is expressedin terms of log 10.

The product to be tested is poured into cupped hands which had beendipped in the contaminated fluid in the same manner described above. Theproduct is rubbed vigorously into the skin up to the wrists for 60seconds to ensure total coverage of the hands. The fingers are thenrinsed under running tap water for 15 seconds and excess water is shakenoff.

The hands are then sampled individually to establish a post treatment or“post-value” count of test organisms. This is performed using exactlythe same method as that used to establish the pre-value count. That is,the fingertips (including the thumb) are rubbed against the base of apetri dish (one for each hand) containing 10 ml TSB in a neutralizationbath for 60 seconds. A series of 10-fold dilutions of the neutralizationbath is prepared and each dilution is plated on a well-dried TSA plateand incubated at 37° C. for 18-24 hours. The number of surviving colonyforming units of microorganisms on each plate is then counted and thevalue is expressed in terms of log 10.

5 ml of a soft soap which does not have any antimicrobial activeingredients, is used as a control and tested in the above same manner.

After recording the number of colony forming units for each dilution ofthe sample neutralization fluid, the number of colony forming units perml is calculated and expressed in terms of log 10. For both test andcontrol products, the mean log counts from left and right hands are usedto determine the pre- and post-values. The difference between the meanpre-value and the mean post-value counts is then calculated and a logreduction factor for the test product and the control product iscalculated using the WILCOXON's ranked pairs test. For a product toconform to standard EN.1499, the log 10 reductions calculated for thetest product must be significantly better (pr=0.01) than thosecalculated for the control product.

Test method EN.12054 is a suspension test method, which entailspipetting 9.0 ml of the test solution into a 25 ml capacity sterilecontainer. 1 ml of a bacterial test suspension is then added and mixedwith the test solution. The container is then placed in a water bath at20±1° C. for a defined contact time. Just before conclusion of thedefined contact time, the solution is mixed and 1.0 ml is transferredinto a tube containing 8 ml of a neutralizer and 1 ml of water. Thesolution is then mixed again and the tube is placed in a water bath at20±1° C. After a neutralization time of 5 minutes ±10 seconds, a seriesof ten-fold dilutions of the neutralized mixture is prepared. A sampleof 1 ml of the mixture and 1 ml of its 10⁻¹ dilution is taken induplicate and incubated by using the pour plate or spread platetechnique. In the pour plate technique, each 1 ml sample of the mixtureis pipetted onto a separate petri dish containing 12 to 15 ml of meltedTSA cooled to 45±1° C. In the spread plate technique, each 1 ml sampleof the mixture is spread on an appropriate number of oven-dried platescontaining TSA.

The plates are then incubated at 36±1° C. for 24 hours after which thenumber of colony forming units for each plate is determined. The platesare incubated for another 24 hours and the colony forming units arerecounted. The highest count value for each plate is used to determinethe effectiveness of the test solution. Results are expressed in termsof log 10. A 3-log reduction is the criteria for passing this testmethod. SOLUTION 2 INGREDIENTS % w/w Actual concentration % w/wdeionized water Up to 100 Up to 100 citric acid Up to Up to pH = 4 pH =4 Glycerin 1 1 BRIQUEST ADPA 60 AW 0.6 0.36 STEPAN MILD SL3 BA 4 1.28AMMONYX LO 0.7 0.21 POLYQUATERNIUM-11 0.8 0.16 hydrogen peroxide 6 3

Solution 2 does not contain any cyclic carboxylic acids and is thereforenot in accordance with the present invention. This solution (at 55%dilution) failed the in vitro European suspension test method EN.12054using a contact time of 1 minute. SOLUTION 3 INGREDIENTS % w/w Actualconcentration % w/w deionized water Up to 100 Up to 100 citric acid 0.10.1 glycerin 1 1 BRIQUEST ADPA 60 AW 0.6 0.36 STEPAN MILD SL3 BA 4 1.28salicylic acid 0.17 0.17 POLYQUATERNIUM-11 0.8 0.16 hydrogen peroxide 63 KOH Up to Up to pH = 4.0 pH = 4.0

Solution 3 does not contain any surfactants which are essential to thepresent invention and is therefore not in accordance with the presentinvention. This solution (at 55% dilution) failed the in vitro Europeansuspension test method EN. 12054 using a contact time of 1 minute.

What follows are additional exemplary solutions according to the presentinvention. SOLUTION 4 5 6 7 8 INGREDIENTS % w/w % w/w % w/w % w/w % w/wdeionized water Qs to 100 hydrogen peroxide 3 4 3 3 3 1.5 2 1.5 1.5 1.5benzoic acid 0.17 0.17 0.15 0.17 0.17 0.17 0.17 0.15 0.17 0.17 BRIQUESTADPA 60 AW 0.5 0.5 0.5 0.5 0.5 0.3 0.3 0.3 0.3 0.3 lactic acid — — — —0.5 — — — — 0.4 DEHYTON MC 0.5 0.5 0.5 0.5 0.5 0.2 0.2 0.2 0.2 0.2AMMONYX CDO — 0.5 0.2 0.5 0.5 — 0.15 0.06 0.15 0.15 MIRANOL C2M CONC NP— — 0.5 0.7 0.7 — — 0.15 0.21 0.21 MERGITAL EL33 2.5 1.0 — — — 0.2250.09 — — — sorbitol — — 2.0 — — — — 2.0 — — glycerin 3.0 — — 2.5 4.0 3.0— — 2.5 4.0 benzyl alcohol — — — — 2.5 — — — — 2.5 isopropyl alcohol — —— 2.0 — — — — 1.4 — NaOH (50%) To To To To To pH = 3.0 pH = 5.5 pH = 5.0pH = 5.0 pH = 4.0 SOLUTION 9 10 11 12 13 INGREDIENTS % w/w % w/w % w/w %w/w % w/w deionized water Qs to 100 hydrogen peroxide 3 4 3 4 3 1.5 21.5 2 1.5 benzoic acid — 0.17 — 0.17 0.17 — 0.17 — 0.17 0.17 salicylicacid — — 0.15 0.02 — — — 0.15 0.02 — 2-furan carboxylic acid 0.5 — — — —0.5 — — — — BRIQUEST 301-50A 0.5 0.5 — — 0.5 0.25 0.25 — — 0.25 VERSENENTA 148 — — — 0.5 — — — — 0.5 — VERSENE 100 — — 0.4 — — — — 0.4 — —MIRANOL C2M CONC NP 25 40 7 10 7.5 12 2.1 3 ETHAL OA-23 — 0.05 0.05 0.10.07 — 0.04 0.04 0.07 0.05 AMMONYX CDO 20 — 10 0.5 6 — 3 0.15 NATRASOL250 HR — — 0.5 — — — — 0.5 — — glycerin — — 5.0 — — — — 5.0 — — benzylalcohol — — — — 2.0 — — — — 2.0 isopropyl alcohol — — — 2.0 — — — — 1.4— NaOH (50%) To To To To To pH = 2.5 pH = 3.5 pH = 5.0 pH = 6.0 pH = 5.0SOLUTION 14 15 16 17 18 INGREDIENTS % w/w % w/w % w/w % w/w % w/wdeionized water Qs to 100 hydrogen peroxide 3 4 3 4 3 1.5 2 1.5 2 1.5benzoic acid — 0.17 — 0.17 0.17 — 0.17 — 0.17 0.17 salicylic acid — —0.15 0.02 — — — 0.15 0.02 — 2-furan carboxylic acid 0.5 — — — — 0.5 — —— — BRIQUEST 301-50A 0.5 0.5 0.5 0.5 0.5 0.25 0.25 0.25 0.25 0.25 citricacid — 1.0 — — — — 1.0 — — — AMPHOSOL CG 0.3 0.5 — 0.7 0.7 0.09 0.15 —0.21 0.21 SURFYNOL 104PG-50 0.1 0.05 0.05 0.1 0.07 0.05 0.03 0.03 0.050.04 AMMONYX LO — — 6.0 0.5 0.5 — — 1.8 0.15 0.15 CARBOPOL 676 0.3 — — —— 0.3 — — — — sorbitol 4.0 — — — — 4.0 — — — — benzyl alcohol — — — —2.0 — — — — 2.0 isopropyl alcohol — — — 2.0 — — — — 1.4 — NaOH (50%) ToTo To To To pH = 2.5 pH = 3.0 pH = 5.0 pH = 6.0 pH = 5.0 SOLUTION 19 2021 22 23 INGREDIENTS % w/w % w/w % w/w % w/w % w/w deionized water Qs to100 hydrogen peroxide 3 4 3 4 3 1.5 2 1.5 2 1.5 benzoic acid — 0.2 —0.15 0.17 — 0.2 — 0.15 0.17 salicylic acid — — 0.15 0.04 — — — 0.15 0.04— 2-furan carboxylic acid 0.3 — — — — 0.3 — — — — BRIQUEST 301-50A 0.40.5 0.5 0.5 0.5 0.2 0.25 0.25 0.25 0.25 citric acid — 1.0 — — — — 1.0 —— — AMPHOTERGE K-2 0.7 0.8 0.8 1.0 0.5 0.28 0.32 0.32 0.4 0.2 AMMONYX LO— — 0.2 0.5 0.5 — — 0.06 0.15 0.15 KLUCEL HF — 0.5 — — — — 0.5 — — —allantoin — 0.05 — — — — 0.05 — — — glycerin 10 4.0 5.0 2.0 3.0 10 4.05.0 2.0 3.0 benzyl alcohol — — — — 2.0 — — — — 2.0 isopropyl alcohol — —— 2.0 — — — — 1.4 — NaOH (50%) To To To To To pH = 2.5 pH = 3.5 pH = 5.0pH = 6.0 pH = 5.0 SOLUTION 24 25 26 27 28 29 INGREDIENTS % w/w % w/w %w/w % w/w % w/w % w/w deionized water Qs to 100 hydrogen peroxide 6 8 88 8 1.0 3 4 4 4 4 0.5 benzoic acid 0.2 0.1 0 0.1 0.1 0.1 0.2 0.1 0 0.10.1 0.1 salicylic acid — 0.1 0.2 0.1 0.1 0.1 — 0.1 0.2 0.1 0.1 0.1BRIQUEST ADPA 60AW 3.0 4.0 4.0 4.0 — 2.4 0.18 2.4 2.4 2.4 — 2.4 VERSENAHEIDA — — — — 4.0 2.5 1.6 1.0 citric acid 1.0 1.0 1.0 1.0 1.0 1.0 1.01.0 1.0 1.0 1.0 1.0 TERGITOL 15-S-7 5.0 7.0 7.0 7.0 7.0 7.0 5.0 7.0 7.07.0 7.0 7.0 TERGITOL 15-S-5 2.0 3.0 3.0 3.0 3.0 3.0 2.0 3.0 3.0 3.0 3.03.0 ETHAL OA-23 0.2 0.1 3.0 1.2 1.2 1.2 0.14 0.07 2.1 0.84 0.84 0.84glycolic acid 2.0 1.0 1.0 1.0 1.0 1.0 1.2 0.6 0.6 0.6 0.6 0.6 phosphoricacid — 1.0 1.0 1.0 1.0 1.0 — 0.75 0.75 0.75 0.75 0.75 AMMONYX LO 3.0 2.02.0 14 5.0 5.0 0.9 0.6 0.6 4.2 1.5 1.5 AMPHOSOL CG 5.0 — — — 5.0 5.0 1.5— — — 1.5 1.5 MONTALINE C40 4.0 — 10 — 4.0 4.0 1.6 — 4.0 — 1.6 1.6MIRANOL C2M CONC NP — — — 7.0 5.0 5.0 — — — 2.1 1.5 1.5 glycerin 3.0 1.02.0 7.0 8.0 4.0 3.0 1.0 2.0 7.0 8.0 4.0 propylene glycol 0 0 0 1.0 1.01.0 0 0 0 1.0 1.0 1.0 NaOH (50%) To pH = 4.0 SOLUTION 30 31 INGREDIENTS% w/w % w/w deionized water Qs to 100 hydrogen peroxide 3 4 1.5 2.0benzoic acid — 0.2 — 0.2 salicylic acid 0.15 — 0.15 — BRIQUEST 301-50A0.4 0.5 0.2 0.25 citric acid — 1.0 — 1.0 LONZAINE 16SP 5.0 — 1.8 —MIRATAINE CBS — 3.0 — 1.3 AMMONYX LO 1.0 0.3 0.3 0.1 CARBOPOL 676 — 0.5— 0.5 allantoin — 0.05 — 0.05 glycerin — 4.0 — 4.0 sorbitol 5.0 — 5.0 —NAOH (50% Up to pH = 4 Up to pH = 5 pH 4 5 SOLUTION 32 33 34 35INGREDIENTS % w/w % w/w % w/w % wlw deionized water Qs to 100 hydrogenperoxide 6 8 6 8 3 4 3 4 benzoic acid 0.17 0.1 0.17 0.1 0.17 0.1 0.170.1 salicylic acid 0.17 0.1 0.17 0.1 0.17 0.1 0.17 0.1 BRIQUEST ADPA60AW 0.35 4.0 — — 0.21 2.4 — — BAYPURE CX — — — 0.5 — — — 0.5 BAYPURE DS— — 0.4 — — — 0.4 — citric acid 0.1 1.0 0.1 1.0 0.1 1.0 0.1 1.0 AMMONYXLO 3.0 2.0 3.0 2.0 0.9 0.6 0.9 0.6 AMPHOSOL CG 6.0 — 6.0 — 1.8 — 1.8 —MONTALINE C40 4.0 — 4.0 — 1.6 — 1.6 — POLYQUATERNIUM-7 0.8 — 0.8 — 0.07— 0.07 — Glycerin 3.0 — 3.0 — 3.0 — 3.0 — NATRASOL 250 HR — 0.5 — 0.5 —0.5 — 0.5 KOH (45%) Up to the specified pH pH 3.0 2.0 4.0 5.0The active concentration in final solution is shown in bold.

Solution 32 was tested for its microbial activity using EN.12054 testmethod at 55% dilution against S.aureus, P.aeruginosa, E.hirae, andE.coli and showed more than 3 log reduction which is the criteria for ahand antiseptic. This solution was also tested against E.coli usingEN.1499 and passed the test.

Solution 32 was also tested for its skin irritation using a patch test.In this study, the solution was put on patches and applied on the skinof 11 volunteers for 48 hours. No irritation was observed after thetest, indicating that the solution is not a skin irritant.

Solution 32 was also tested for its hydrogen peroxide stability using ahot stability test method. The solution was kept at 70° C. for one week,which is equivalent to 1 year at room temperature. The loss for hydrogenperoxide was less than 5% proving remarkable stability of the solution.

The foregoing description is by way of example only and shall not beconstrued to limit the scope of the invention as defined by thefollowing claims.

1. An aqueous skin disinfecting solution having a pH of from about 2 toabout 6 and comprising: (a) hydrogen peroxide in a concentration of fromabout 0.01 to about 4% w/w of the solution; (b) at least one surfactantchosen from imidazoline derivatives, alkyl betaines, alkyl amidopropylbetaine amides, alkyl amidopropyl betaines, alkylsulfo betaines, amineoxides and derivatives thereof in a concentration of from about 0.01 toabout 15% w/w of the solution; (c) at least one hydrogen peroxidestabilizer in a concentration of from about 0.01 to about 4% w/w of thesolution; (d) at least one member chosen from cyclic carboxylic acidsand salts thereof in a concentration of from about 0.01 to about 4% w/wof the solution; and (e) at least one skin conditioning agent in aconcentration of from about 0.01 to about 10% w/w of the solution. 2.The solution of claim 1, wherein the imidazoline derivatives are chosenfrom alkylamphocarboxylates and alkyliminocarboxylates.
 3. The solutionof claim 1, wherein the hydrogen peroxide stabilizer is chosen fromphosphoric acid, phosphonic acids having 1 to 5 phosphonic acid groups,ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaaceticacid (DTPA), N-(hydroxyethyl)-ethylenediaminetriacetic acid (HEDTA),nitrilotriacetic acid (NTA), 2-hydroxyethyliminodiacetic acid (HEIDA),benzoic acid, aminobenzoic acid, citric acid, iminodisuccinic acid,polyaspartic acid, and salts thereof.
 4. The solution of claim 3,wherein the hydrogen peroxide stabilizer is chosen from sodiumtripolyphosphate, 1-hydroxyethylidene-1,1,-diphosphonic acid, aminotri(methylene phosphonic acid), diethylenetriaminepenta(methylenephosphonic acid), 2-hydroxy ethylimino bis(methylene phosphonic acid),and ethylene diamine tetra(methylene phosphonic acid).
 5. The solutionof claim 1, wherein the carboxylic acid is chosen from furan carboxylicacid, benzoic acid and salicylic acid.
 6. The solution of claim 5,comprising 2-furan carboxylic acid.
 7. The solution of claim 1, whereinthe skin conditioning agent is chosen from glycerides, sorbitol, castoroil, allantoin, cationic polymers, lanolin and its derivatives and cetylalcohol.
 8. The solution of claim 1, comprising at least one buffer in aconcentration of from about 0.01 to about 5% w/w of the solution.
 9. Thesolution of claim 8, wherein the buffer is chosen from citric acid,lactic acid, glycolic acid, phosphoric acid, malic acid, succinic acidand tartaric acid.
 10. The solution of claim 1, comprising at least onehydrogen peroxide compatible surfactant in a concentration of from about0.01 to about 10% w/w of the solution.
 11. The solution of claim 1,comprising at least one C1 to C8 alcohol chosen from benzyl alcohol,ethanol, n-butanol, isopropanol, glycols in a concentration of fromabout 0.01 to about 10% w/w of solution.
 12. The solution of claim 1,comprising at least one thickening agent compatible with hydrogenperoxide in a concentration of from about 0.01 to about 5% w/w of thesolution.
 13. The solution of claim 12, wherein the thickening agent ischosen from polyacrylic acid polymers, polysaccharides, and cellulosebased polymers.
 14. The solution of claim 1, comprising at least onemember chosen from dyes and fragrances in a concentration of from about0.001 to about 0.5% w/w of the solution.
 15. The solution of claim 1,wherein the pH is from about 2.5 to about
 5. 16. The solution of claim1, wherein the hydrogen peroxide is present in a concentration of fromabout 0.25 to about 3% w/w of the solution.
 17. The solution of claim 1,further comprising at least one member chosen from monocarboxylic acids,polycarboxylic acids, and mixtures thereof in a concentration of fromabout 0.01 to about 3% w/w of the solution.
 18. An aqueous skindisinfecting solution having a pH of from about 2.5 to about 5 andcomprising: (a) hydrogen peroxide in a concentration of from about 1 toabout 3% w/w of the solution; (b) at least one surfactant chosen fromalkyl betaines, alkyl amidopropyl betaines, alkyl amidopropyl betaineamides, alkylsulfo betaines, alkyl amphocarboxylates,alkyliminocarboxylates, amine oxides and derivatives thereof in aconcentration of from about 1 to about 5% w/w of the solution; (c) atleast one hydrogen peroxide stabilizer in a concentration of from about0.01 to about 2% w/w of the solution; (d) at least one member chosenfrom cyclic carboxylic acids and salts thereof in a concentration offrom about 0.05 to about 1 % w/w of the solution; and (e) at least oneskin conditioning agent in a concentration of from about 0.5 to about 4%w/w of the solution.
 19. A concentrated skin disinfectant solution,which can be diluted with water to form the solution of claim
 1. 20. Adry powdered formulation, which can be dissolved in water to form thesolution of claim 1.